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Abstract:

A coating forming composition that includes: (a) a silane derivative of
Formula (I)
##STR00001## wherein R1, R2, R3 and R4 that can
be the same or different are selected from alkyl, acyl, alkylene acyl,
cycloalkyl, aryl or alkylene aryl that can where necessary be
substituted, and/or a hydrolysis product and/or condensation product of
the silane derivative of Formula (I), (b) a silane derivative of
Formula (II)
R6R73-nSi(OR5)n (II) wherein R5 is an
unsubstituted or substituted alkyl, acyl, alkylene acyl, cycloalkyl, aryl
or alkylene aryl group, R6 is an organic residue that contains an
epoxide group, R7 is an unsubstituted or substituted alkyl,
cycloalkyl, aryl or alkylene aryl group, n is 2 or 3, and/or a
hydrolysis product and/or condensation product of the silane derivative
of Formula (II), (c) a colloidal inorganic oxide, fluoride or
oxyfluoride, (d) a cycloaliphatic or aromatic epoxide, and (e) a solvent.

Claims:

1. A composition for the manufacture of a coating, comprising: (a) One or
more of the following: 1) a silane derivative of Formula (I)
##STR00005## whereby R1, R2, R3 and R4 that can be
the same or different are selected from alkyl, acyl, alkylene acyl,
cycloalkyl, aryl or alkylene aryl that can be substituted where
necessary; 2) at least one hydrolysis product of the silane derivative of
Formula (I); and 3) at least one condensation product of the silane
derivative of Formula (I); (b) One or more of the following: 1) a silane
derivative of Formula (II) R6R.sup.7.sub.3-nSi(OR5)n
(II) wherein R5 is an unsubstituted or substituted alkyl, acyl,
alkylene acyl, cycloalkyl, aryl or alkylene aryl group, R6 is an
organic residue that contains an epoxide group, R7 is an
unsubstituted or substituted alkyl, cycloalkyl, aryl or alkylene aryl
group, n is 2 or 3, 2) at least one hydrolysis product of the silane
derivative of Formula (II); and 3) at least one condensation product of
the silane derivative of Formula (II); (c) at least one of the following:
a colloidal inorganic oxide, a colloidal inorganic fluoride; and a
colloidal inorganic oxyfluoride; (d) at least one or the following: a
cycloaliphatic or aromatic epoxide compound that has at least two epoxide
groups; and (e) a solvent that contains an alcohol, ether and/or ester.

2. The composition according to claim 1, wherein at least one of: the
silane derivative of Formula (I); the hydrolysis product(s) of the silane
derivative of Formula (I); and the condensation product(s) of the silane
derivative of Formula (I) is or are present in the composition in an
amount of 1% by weight to 35% by weight of the composition.

3. The composition according to claim 1, wherein the residue R6 in
the silane derivative of Formula (II) has the following Formula (III):
##STR00006## wherein R8 is hydrogen or C1-4-alkyl; and R9
is C1-10-alkylene.

4. The composition according to claim 2, whereby the residue R6 in
the silane derivative of Formula (II) has the following Formula (III):
##STR00007## wherein R8 is hydrogen or C1-4-alkyl; and R9
is C1-10-alkylene.

5. The composition according to claim 1, wherein the silane derivatives
of Formula (II); the hydrolysis product(s) of the silane derivative of
Formula (II); and the condensation product(s) of the silane derivative of
Formula (II) is or are present in the composition in an amount of 1%
weight to 35% weight.

6. The composition according to claim 2, wherein the silane derivatives
of Formula (II); the hydrolysis product(s) of the silane derivative of
Formula (II); and the condensation product(s) of the silane derivative of
Formula (II) is or are present in the composition in an amount of 1%
weight to 35% weight.

7. The composition according to claim 1, wherein the weight ratio of X to
Y is in the range of 95/5 to 5/95; wherein X is the silane derivative of
Formula (I); the hydrolysis product(s) of the silane derivative of
Formula (I); and the condensation product(s) of the silane derivative of
Formula (I) and Y is the silane derivatives of Formula (II); the
hydrolysis product(s) of the silane derivative of Formula (II); and the
condensation product(s) of the silane derivative of Formula (II).

8. The composition according to claim 2, wherein the weight ratio of X to
Y is in the range of 95/5 to 5/95; wherein X is the silane derivative of
Formula (I); the hydrolysis product(s) of the silane derivative of
Formula (I); and the condensation product(s) of the silane derivative of
Formula (I) and Y is the silane derivatives of Formula (II); the
hydrolysis product(s) of the silane derivative of Formula (II); and the
condensation product(s) of the silane derivative of Formula (II).

9. The composition according to claim 5, wherein the weight ratio of X to
Y is in the range of 95/5 to 5/95; wherein X is the silane derivative of
Formula (I); the hydrolysis product(s) of the silane derivative of
Formula (I); and the condensation product(s) of the silane derivative of
Formula (I) and Y is the silane derivatives of Formula (II); the
hydrolysis product(s) of the silane derivative of Formula (II); and the
condensation product(s) of the silane derivative of Formula (II).

10. The composition according to claim 6, wherein the weight ratio of X
to Y is in the range of 95/5 to 5/95; wherein X is the silane derivative
of Formula (I); the hydrolysis product(s) of the silane derivative of
Formula (I); and the condensation product(s) of the silane derivative of
Formula (I) and Y is the silane derivatives of Formula (II); the
hydrolysis product(s) of the silane derivative of Formula (II); and the
condensation product(s) of the silane derivative of Formula (II).

11. The composition according claim 1, wherein the colloidal inorganic
oxide is selected from the group comprising SiO2, TiO2,
ZrO2, SnO2, Sb2O3, Al2O3, AlO(OH), mixed
oxides, mixtures thereof, and core shell structures thereof; and the
colloidal inorganic fluoride is MgF2 that is optionally present in
the core shell structure with the inorganic oxide.

12. The composition according to claim 11, wherein the total of the
colloidal inorganic oxide, the colloidal inorganic oxide fluoride and the
colloidal inorganic oxide oxyfluoride is in an amount of 1% weight to 25%
weight based on the total weight of the composition.

13. The composition according to claim 11, wherein the total of the
colloidal inorganic oxide, the colloidal inorganic oxide fluoride and the
colloidal inorganic oxide oxyfluoride is in an amount of 1% weight to 25%
weight based on the total weight of the composition.

14. The composition according to claim 13, wherein the cycloaliphatic or
aromatic epoxide compound has at least two substituents that can be the
same or different and that are represented by the following formula:
##STR00008## wherein R8 is hydrogen or C1-4-alkyl, R9 is
an unsubstituted or substituted C1-10-alkylene group, preferably an
unsubstituted or substituted C1-4-alkylene group; k is 1-4; and m is
0 or 1.

15. The composition according to claim 1, wherein the cycloaliphatic or
aromatic epoxide compound has at least two substituents that can be the
same or different and that are represented by the following formula:
##STR00009## wherein R8 is hydrogen or C1-4-alkyl, R9 is
an unsubstituted or substituted C1-10-alkylene group, preferably an
unsubstituted or substituted C1-4-alkylene group; k is 1-4; and m is
0 or 1.

16. The composition according to claim 15, wherein the cycloaliphatic or
aromatic compound that has at least two epoxide groups is present in an
amount of 0.1% weight to 20% weight based on the total weight of the
composition.

17. The composition according to claim 1, wherein the solvent contains is
chosen from the group consisting of an alcohol that is selected from a
C1-6-alkanol, preferably a C1-4-alkanol, a mono-C1-4-alkyl
ether of a C2-4-alkylene glycol, a mixture of the preceding
alcohols; a dialkyl ether, a cycloaliphatic ether, an aryl ether, an
alkyl aryl ether, an alkyl ester, a cycloalkyl ester, an aryl alkyl ester
and an alkylene glycol ester.

18. The composition according to claim 1, wherein the solvent contains a
first alcohol, ether or ester with a boiling point Si and a second
alcohol, ether or ester with a boiling point S2, whereby the boiling
point S1 and the boiling point S2 vary such that either S1/S2.gtoreq.1.2
or S1/S2.ltoreq.0.8.

19. The composition according to claim 1 further comprising a catalyst
for the thermal polymerization of epoxides.

20. A method for coating a substrate comprising the following steps:
providing a composition according to claim 1; applying the composition to
the substrate; and forming a cured coating by heating the composition
applied to the substrate at a temperature in the range of 75.degree. C.
to 150.degree. C. to cure the coating.

21. An article comprising: a substrate; and a cured coating on the
surface of the substrate, wherein a composition according to claim 1
which has been heated on the substrate surface at a temperature in the
range of 75.degree. C. to 150.degree. C. forms the cured coating on the
substrate surface.

Description:

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application
Ser. No. 61/331,877, entitled Composition for the Preparation of an
Abrasion Resistant Coating with Improved Caustic Resistance, filed on May
6, 2010, the entire disclosure of which is hereby incorporated by
reference. This application also claims priority to German application
No. DE 10 2010 028 661.2, filed on May 6, 2010, the entire disclosure of
which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] Transparent polymers are increasingly being used in the area of
optics and optoelectronics, as these materials offer advantages in terms
of weight reduction and resistance to breaks. Components with more
complex three-dimensional geometry, such as lenses and lens elements, can
also be manufactured in relatively large quantities in the area of
precision optics.

[0003] Example plastic materials currently being used in optics include
polymethyl-methacrylate, polycarbonate, diethylene glycol bis allyl
carbonate (trade name CR39®) and special, highly refractive polymers
based on polythiourethane.

[0004] One of the disadvantages of these plastic materials is their
relatively low surface hardness and scratch-resistance.

[0005] A well-known approach for improving scratch-resistance involves
applying a surface coating as part of a sol-gel process. Here, it is
possible to use tetra-alkoxysilanes, which hydrolyse under suitable
conditions, and which result in a three-dimensionally networked silicate
structure once the silanol groups created by the hydrolysis have
undergone condensation.

[0006] In addition to having the highest possible degree of scratch
resistance, the surface coating should also meet a series of other
requirements. These include having the lowest possible tendency to crack
under thermal exposure, adhering as strongly as possible to the substrate
surface, and being as resistant as possible to acids and/or bases.
Furthermore, the coating's refractive index should be capable of being
adapted to that of the substrate as much as possible.

[0007] When fulfilling these criteria, however, it must be taken into
account that these properties very often counteract one another, so one
is usually only improved at the price of another.

[0008] To increase the flexibility of the silicate network, and thus
reduce its tendency to crack under thermal exposure, the
tetra-alkoxysilanes are often used in combination with
organo-alkoxysilanes (i.e. silanes which, apart from alkoxy groups, also
display one or more organic residues bonded directly to the Si atom).
Although the resulting organic-inorganic network structure has greater
flexibility and base stability, this is achieved at the price of a lower
degree of hardness compared to the purely inorganic silicate network.

[0009] U.S. Pat. No. 3,986,997 describes an aqueous composition containing
colloidal SiO2, as well as an organo-trialkoxysilane, such as
methyltrimethoxysilane, and/or products resulting from the hydrolysis
and/or condensation this organo-trialkoxysilane.

[0010] It is also known to use tetra-alkoxysilane or colloidal SiO2,
as well as an organo-alkoxysilane whose organic residue contains an epoxy
group, to be used in combination with a dicarboxylic acid or a
dicarboxylic acid anhydride.

[0011] US 2001/0049023 A1 discloses a composition for coating a substrate
based on a mixed aqueous organic solvent containing (i) an
organo-alkoxysilane with epoxide functions or the products resulting from
the hydrolysis and/or condensation of this organo-alkoxysilane, (ii) a
tetra-alkoxysilane or the products resulting from the hydrolysis and/or
condensation of this tetra-alkoxysilane and (iii) a dicarboxylic acid or
dicarboxylic acid anhydride.

[0012] The use of tetra-alkoxysilane/colloidal SiO2, as well as an
organo-alkoxysilane whose organic residue contains an epoxy group,
combined with a dicarboxylic acid or dicarboxylic acid anhydride is also
discussed in U.S. Pat. No. 4,355,135 and U.S. Pat. No. 5,322,888.

[0013] WO 2008/087741 discloses a coating composition containing (A) a
poly(methyl) glycidyl ether compound with aliphatic residue R1, (B) a
silsesquioxane, (C) an alkoxy compound, (D) an organo-alkoxy compound
whereby the organic residue bonded to the Si atom has a cationically
polymerisable group such as an epoxy group, and (E) a photopolymerization
catalyst. With regards to suitable multi-functional epoxy compounds as
component (A), WO 2008/087741 states that cyclic epoxy compounds, i.e.
cycloaliphatic and aromatic epoxy compounds, are not suitable for
manufacturing sufficiently hard coatings.

[0014] Taking into account the above information, it is an object of an
embodiment of the present invention to provide a composition enabling
production of a coating which achieves a better compromise in terms of
high scratch resistance with low tendency to crack under thermal
exposure, good adhesion to the substrate surface, and high resistance to
acids and/or bases.

[0016] ##STR00002## [0017] where [0018] R1, R2, R3 and
R4, that can be the same or different, are selected from alkyl,
acyl, alkylene acyl, cycloalkyl, aryl or alkylene aryl, which can be
substituted if necessary, [0019] and/or a hydrolysis product and/or
condensation product of the silane derivative of Formula (I), [0020]
(b) a silane derivative with Formula (II)

[0030] In accordance with a further aspect of this invention, a method for
coating a substrate is provided that includes:

[0031] providing the composition described above;

[0032] applying the composition to the substrate; and

[0033] treating the substrate at a temperature in the range of 75°
C. to 150° C. for curing of the coating.

[0034] In accordance with a further aspect of this invention, an article
is provided that includes: [0035] a substrate; and [0036] a coating on
the substrate surface, whereby the coating is obtainable or is obtained
through the above-mentioned method.

[0037] In accordance with a further aspect, this invention concerns the
use of the above mentioned composition to coat a substrate.

[0038] These and other features, advantages, and objects of the present
invention will be further understood and appreciated by those skilled in
the art by reference to the following specification, claims, and appended
drawings.

DETAILED DESCRIPTION

[0039] It is to be understood that the invention may assume various
alternative embodiments, except where expressly specified to the
contrary. It is also to be understood that the specific compositions and
processes described in the following specification are simply exemplary
embodiments of the inventive concepts defined in the appended claims.
Hence, specific embodiments disclosed herein are not to be considered as
limiting, unless the claims expressly state otherwise.

[0040] As described in further detail below, using a composition
containing components (a) to (e) enables production of a coating having
by a high degree of scratch resistance, a high resistance to bases, good
adhesive strength, and a low tendency for cracking.

[0041] As stated above, the composition according to this invention
contains a silane derivative with Formula (I) and/or a hydrolysis product
and/or condensation product of said silane derivative as component (a).

[0042] The term "a hydrolysis product and/or condensation product of the
silane derivative of Formula (I)" indicates that, as part of an aspect of
this invention, it is also possible for the silane derivative (I) to have
been at least partly hydrolyzed by forming silanol groups, and for the
condensation reaction of these silanol groups to have already established
a certain degree of cross-linking.

[0043] If R1, R2, R3 and/or R4 is/are an alkyl group,
this will preferably involve a C1-8 alkyl group, or more preferably
a C1-4 alkyl group, which can still be substituted if necessary. For
example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl,
tert-butyl, hexyl or octyl can be used here.

[0051] These silane derivatives with Formula (I) are generally known to
the skilled person, are commercially available and/or can be made using
standard processes familiar to the skilled person.

[0052] The silane derivatives with Formula (I) and/or the products
resulting from the hydrolysis and/or condensation of said silane
derivatives are present in the composition in an amount of 1% by weight
to 35% by weight, preferably 5% by weight to 20% by weight.

[0053] As stated above, the composition according to this invention
contains a silane derivative with Formula (II) and/or a product resulting
from the hydrolysis and/or condensation of said derivative as component
(b).

[0054] The term "the hydrolysis product and/or condensation product of the
silane derivative of Formula (II)" once again indicates that, as part of
this invention, it is also possible for the silane derivative (II) to
have been at least partly hydrolyzed by forming silanol groups, and for
the condensation reaction of these silanol groups to have already
established a certain degree of cross-linking.

[0055] See the above information for residues R1, R2, R3
and R4 with regards to the preferred alkyl, acyl, alkylene acyl,
cycloalkyl, aryl or alkylene aryl groups of residue R5.

[0057] The epoxy group in residue R6 preferably exists in the form of
a glycidoxy group, which is preferably bonded to the silicon atom by a
C1-10-alkylene group, preferably a C1-4-alkylene group, e.g.
ethylene, propylene or butylene, an arylene group, e.g. phenylene, or an
alkyleneether group.

[0058] Preferably, the residue R6 has the following Formula (III):

##STR00003##

[0059] where

[0060] R8 is hydrogen or C1-4-alkyl, preferably hydrogen, and

[0061] R9 is an unsubstituted or substituted C1-10-alkylene
group, preferably an unsubstituted or substituted C1-4-alkylene
group.

[0062] As mentioned above, an alkylene group is understood as being a
bivalent alkyl group (i.e. --CH2--; --CH2--CH2--; etc.).

[0063] See the above information for residues R1, R2, R3
and R4 with regards to the preferred alkyl, cycloalkyl, aryl or
alkylene aryl groups of residue R7.

[0065] These silane derivatives of Formula (II) are generally known to the
skilled person and are commercially available and/or can be manufactured
through standard methods known to the skilled person.

[0066] Preferably the silane derivative of Formula (II) and/or the
hydrolysis products and/or condensation products of the silane derivative
(II) is/are present in the composition in an amount of 1% weight to 35%
weight, and preferably of 5% weight to 20% weight.

[0067] The weight ratio of the silane derivative (I) or its hydrolysis
products and/or condensation products to the silane derivative (II) can
in principle be varied over a wide range.

[0068] Preferably the weight ratio of the silane derivative (I) and/or its
hydrolysis products and/or condensation products to the silane derivative
(II) and/or its hydrolysis products and/or condensation products is in
the range of 95/5 to 5/95 more, preferably in the range of 70/30 to
30/70, and even more preferably in the range of 60/40 to 40/60.

[0069] As already mentioned above, the composition in accordance with the
invention as component (c) contains a colloidal inorganic oxide, fluoride
or oxyfluoride or a mixture of these.

[0070] The colloidal inorganic oxide, fluoride or oxyfluoride contributes
to the increase in scratch resistance through incorporation into the
existing network. Furthermore, by selecting suitable oxides, fluorides or
oxyfluorides, the refractive index of the coating can be adjusted to the
refractive index of the substrate.

[0071] In a preferred embodiment, the inorganic oxide is selected from of
SiO2, TiO2, ZrO2, SnO2, Sb2O3,
Al2O3, AlO(OH) or mixed oxides or mixtures or core shell
structures thereof. As fluoride, for example, MgF2 can be used as a
pure component or in a core shell structure with one of the
above-mentioned oxides.

[0072] The mean particle diameter of the inorganic component should
preferably be selected in such a way that the transparency of the coating
is not affected. In a preferred embodiment, the colloidal inorganic
component has a mean particle diameter in the range of 2 nm to 150 nm,
and even more preferably of 2 nm to 70 nm. The mean particle diameter is
measured through dynamic light scattering.

[0073] Preferably the colloidal inorganic component is present in an
amount of 1% weight to 40% weight, and even more preferably of 5% weight
to 25% weight, based on the total weight of the composition.

[0074] As already mentioned above, the composition in accordance with the
invention contains as component (d) a cycloaliphatic or aromatic epoxide
compound that has at least two epoxide groups.

[0075] This can for example also be a prepolymer with 2 or more epoxy
functionalities.

[0076] Within the scope of this invention it is therefore essential that
the epoxide compound of component (d) has a cyclic group, either in the
form of a cycloaliphatic or an aromatic unit.

[0077] As discussed further below, the use of a cycloaliphatic or aromatic
epoxide compound in comparison to a non-cyclic epoxide compound leads to
an improved compromise between scratch resistance, resistance to bases
and bonding strength on the substrate.

[0078] Preferably the cycloaliphatic compound is a substituted cyclohexane
or substituted cyclopentane that has at least two substituents with at
least one epoxide group each, or a mixture of these epoxide compounds, or
a prepolymer of this compound.

[0079] Preferably the aromatic compound is a substituted benzene,
substituted diphenylmethane derivative or substituted bisphenol that has
at least two substituents with at least one epoxide group each, or a
mixture of these epoxide compounds, or a prepolymer of this compound.

[0080] Preferably the cycloaliphatic or aromatic epoxide compound has at
least two substituents that can be the same or different and that are
represented by the following formula:

##STR00004##

[0081] wherein

[0082] R8 has the meaning already indicated above (i.e. hydrogen or
C1-4-alkyl) and

[0086] Resorcinol bisglycidyl ether and cyclohexandimethanol bisglycidyl
ether or their mixtures can e.g. be mentioned as preferred cycloaliphatic
or aromatic epoxide compounds that have at least two epoxide groups.

[0087] Preferably the cycloaliphatic or aromatic compound that has at
least two epoxide groups is present in an amount of 0.1% weight to 20%
weight, preferably of 0.5% weight to 10% weight, based on the total
weight of the composition.

[0088] As already mentioned above, the composition in accordance with the
invention comprises as component (e) a solvent that contains an alcohol,
ether and/or ester.

[0089] If the solvent contains an alcohol, this is preferably selected
from an alkanol, cycloalkanol, aryl alcohol, alkylene glycol, monoalkyl
ether of polyoxyalkylene glycols or monoalkyl ether of alkylene glycols
or their mixtures.

[0090] Preferably, the alcohol is selected from a C1-6-alkanol, more
preferably a C1-4-alkanol, a mono-C1-4-alkyl ether of a
C2-4-alkylene glycol, or a mixture thereof.

[0091] If the solvent contains an ether, this is preferably selected from
a dialkyl ether, a cycloaliphatic ether, an aryl ether or alkyl aryl
ether or their mixtures.

[0092] If the solvent contains an ester, this is preferably selected from
an alkyl ester, cycloalkyl ester, aryl alkyl ester, alkylene glycol ester
or their mixtures.

[0093] With regard to the homogeneity and optical quality of the coating
manufactured from the composition, it can be advantageous if the solvent
contains two alcohols, ethers or esters with different boiling points.

[0094] Preferably the solvent contains a first alcohol, ether or ester
with a boiling point S1 and a second alcohol, ether or ester with a
boiling point S2, whereby the boiling point S1 and the boiling point S2
vary in such a way that either

S1/S2≧1.2

or

S1/S2≦0.8

[0095] Preferably the solvent contains a C1-4-alkanol as the first
alcohol and a monoalkyl ether of an alkylene glycol, preferably a
mono-C1-4-alkyl ether of a C2-4-alkylene glycol as the second
alcohol.

[0096] Preferably the weight ratio of the first alcohol to the second
alcohol is in the range of 5 to 0.01, and preferably in the range of 2 to
0.2.

[0097] Preferably the composition also contains water. In a preferred
embodiment, the water is present in an amount of 2 to 15% weight, based
on the total weight of the composition.

[0098] Preferably, the composition in accordance with the invention also
contains a catalyst for epoxide polymerization.

[0099] Within the scope of this invention, both a catalyst for the photo
polymerization and a catalyst for the thermal polymerization of epoxides
can be used. Both catalyst groups are in principle well known to the
expert.

[0100] In a preferred embodiment, the composition contains a catalyst for
the thermal polymerization of epoxides but no catalyst for the photo
polymerization of epoxides.

[0101] As a catalyst for the thermal polymerization of epoxides, the
compounds known to the expert for this purpose can be used.

[0102] Preferably the catalyst comprises a Lewis acid.

[0103] For example, the following can be mentioned as suitable catalysts
for the thermal polymerization of epoxides:

[0105] Preferably the catalyst is present in an amount in the range of
0.01% weight to 5% weight, and preferably in the range of 0.1% weight to
3% weight, based on the total weight of the composition.

[0106] As other optional components of the composition, surfactants (e.g.
to assist with film formation), UV-absorbers, dyes and/or stabilisers can
be mentioned.

[0107] For the coating procedure it can be advantageous if the silanes of
Formula (I) and/or (II) already have a certain cross-linkage at the time
of their application to the substrate. A defined pre-condensation can
e.g. be achieved through hydrolysis of the silanes of Formula I and/or II
catalysed with water or an aqueous organic or mineral acid.

[0108] The composition can be applied to the substrate through methods
known to the expert.

[0109] For example, dip coating, spin coating, spray coating, flooding and
slit nozzle application can be mentioned in this context.

[0110] With dip coating, the composition in accordance with the invention
can also be applied to surfaces of substrates with more complex geometry.

[0111] Within the scope of this invention, a large number of different
substrates can be used. Plastic substrates or even glass substrates can
e.g. be coated with the composition in accordance with the invention.

[0112] A suitable plastic substrate can e.g. have one or more of the
following plastics:

[0114] In the case of the substrate to be coated, these are preferably
those used in optical applications.

[0115] Preferably for the substrate this is a lens for application as
plastic eyeglass glass or a magnifying glass.

[0116] Preferably the substrate is thermally treated at a temperature in
the range of 75° C. to 150° C., and even more preferably in
the range of 90° C. to 130° C.

EXAMPLES

Chemicals

IPA-ST: SiO2-Nano-Sol by Nissan Chemicals, Houston

[0117] FC4430: Flow agent of the firm 3M Other chemicals and solvents:
Aldrich

Test Methods

Test of Resistance to Bases:

[0118] Coated glasses (-2.0 dioptres) were treated in an alkaline solvent
(pH>14) at 50° C. with ultrasound for 180 seconds. Layer
thicknesses before and after the treatment were measured optically in the
same spot. The thickness of the hard layers was typically 2.5 μm. The
base resistance is then measured using layer degradation, whereby the
less the layer degradation, the better the base resistance.

[0119] The Bayer test to evaluate the scratch resistance was measured with
a COLTS Bayer-test device and the appropriate method.

[0120] Layer bonding was evaluated via a lattice cutting test.

Example 1

[0121] 36 parts of resorcinol bisglycidyl ether were dissolved in 162
parts of 2-propanol and 264 parts of 1-methoxy-2-propanol. 186 parts of
3-glycidoxypropyl trimethoxysilane, 150 parts of tetraethoxysilane, 240
parts of IPA-ST and 126 parts of water were added to the solution and
agitated at room temperature for 24 hours. After that 7.2 parts of
aluminium acetylacetonate, 25.2 parts of ammonium perchlorate 1M
solution, and 3.6 parts of FC4430 were added and the mixture was agitated
for a further 3 hours. The resultant solution was filtered through a 5
μm filter and stored in the refrigerator before the coating.

Example 2

[0122] 36 parts of 1,4-cyclohexandimethanol diglycidyl ether were
dissolved in 162 parts of 2-propanol and 264 parts of
1-methoxy-2-propanol. 186 parts of 3-glycidoxypropyl trimethoxysilane,
150 parts of tetraethoxysilane, 240 parts of IPA-ST and 126 parts of
water were added and agitated at room temperature for 24 hours. After
that 7.2 parts of aluminium acetylacetonate, 25.2 parts of ammonium
perchlorate 1M solution, and 3.6 parts of FC4430 were added and the
mixture was agitated for a further 3 hours. The resultant solution was
filtered through a 5 μm filter and stored in the refrigerator before
the coating.

COMPARATIVE EXAMPLE 1

[0123] 36 parts of trimethylolpropane triglycidyl ether were dissolved in
162 parts of 2-propanol and 264 parts of 1-methoxy-2-propanol. 186 parts
of 3-glycidoxypropyl trimethoxysilane, 150 parts of tetraethoxysilane,
240 parts of IPA-ST and 126 parts of water were added and agitated at
room temperature for 24 hours. After that 7.2 parts of aluminium
acetylacetonate, 25.2 parts of 1M ammonium perchlorate solution, and 3.6
parts of FC4430 were added and the mixture was agitated for a further 3
hours. The resultant solution was filtered through a 5 μm filter and
stored in the refrigerator before the coating.

COMPARATIVE EXAMPLE 2

[0124] 36 parts of pentaerythritol tetraglycidyl ether were dissolved in
162 parts of 2-propanol and 264 parts of 1-methoxy-2-propanol. 186 parts
of 3-glycidoxypropyl trimethoxysilane, 150 parts of tetraethoxysilane,
240 parts of IPA-ST and 126 parts of water were added to the solution and
agitated at room temperature for 24 hours. After that 7.2 parts of
aluminium acetylacetonate, 25.2 parts of 1M ammonium perchlorate
solution, and 3.6 parts of FC4430 were added and the mixture was agitated
for a further 3 hours. The resultant solution was filtered through a 5
μm filter and stored in the refrigerator before the coating.

COMPARATIVE EXAMPLE 3

[0125] 186 parts of 3-glycidoxypropyl trimethoxysilane, 186 parts of
tetraethoxysilane, and 240 parts of IPA-ST were mixed in 162 parts of
2-propanol, 264 parts of 1-methoxy-2-propanol and 126 parts of water and
agitated at room temperature for 24 hours. After that 7.2 parts of
aluminium acetylacetonate, 25.2 parts of 1M ammonium perchlorate solution
and 3,6 parts of FC4430 were added and the mixture was agitated for a
further 3 hours. The resultant solution was filtered through a 5
μm-filter and stored in the refrigerator before the coating.

[0126] The test substrates were activated before the dip coating with an
aqueous-alkaline washing process and after the coating cured in an oven
at 95° C. for 4 hours.

[0127] The coatings obtained with these compositions were tested for their
base resistance (determined via the extent of layer degradation) and
their scratch resistance (Bayer-Test). The results obtained are set out
in Table 1.

[0128] The results show that a coating with a high resistance to bases and
very good scratch resistance is obtained with the compositions in
accordance with the invention.

[0129] With the aid of the following examples, the crack formation and
bonding of the coatings in accordance with the invention was tested on
various substrates.

Example 3

[0130] 36 parts of resorcinol bisglycidyl ether were dissolved in 160
parts of 2-propanol and 265 parts of 1-methoxy-2-propanol. 240 parts of
3-glycidoxypropyl trimethoxysilane, 122 parts of tetraethoxysilane, 216
parts of IPA-ST and 126 parts of water were added to the solution and
agitated at room temperature for 24 hours. After that 6 parts of
aluminium acetylacetonate, 25.2 parts of 1M ammonium perchlorate solution
and 3.6 parts of FC4430 were added and the mixture was agitated for a
further 3 hours. The resultant solution was filtered through a 5 μm
filter and stored in the refrigerator before the coating.

Example 4

[0131] 69 parts of resorcinol bisglycidyl ether were dissolved in 160
parts of 2-propanol and 265 parts of 1-methoxy-2-propanol. 227 parts of
3-glycidoxypropyl trimethoxysilane, 102 parts of tetraethoxysilane, 216
parts of IPA-ST and 126 parts of water were added to the solution and
agitated at room temperature for 24 hours. After that 6 parts of
aluminium acetylacetonate, 25.2 parts of 1M ammonium perchlorate solution
and 3.6 parts of FC4430 were added and the mixture was agitated for a
further 3 hours. The resultant solution was filtered through a 5 μm
filter and stored in the refrigerator before the coating.

[0132] The coatings obtained from these compositions were tested for their
primary bonding and their resistance to cracking. The results obtained
are shown in Table 2.

[0133] These examples demonstrate that, with the compositions in
accordance with the invention, coatings are obtained that show a very
good substrate bonding and at the same time have very good base
resistance (no layer degradation) and resistance to cracking.

Patent applications by Bin Peng, Aalen DE

Patent applications by Joerg Puetz, Aalen DE

Patent applications by Norbert Hugenberg, Aalen DE

Patent applications by CARL ZEISS VISION AUSTRALIA HOLDINGS LTD

Patent applications by CARL ZEISS VISION GMBH

Patent applications in class Solid polymer derived from reactant containing element other than C, H, O, or N or chlorine-containing reactant of three or more carbon atoms

Patent applications in all subclasses Solid polymer derived from reactant containing element other than C, H, O, or N or chlorine-containing reactant of three or more carbon atoms